Clutch control



'5. J. PANISH CLUTCH CONTROL Oct. 23, 1945.

Filed Aug. 29, 1941 3 Sheets-Sheet 1 INVENTOR I'm/l2 .[fi

ATTORNEYS Oct. 23, 1945. E. J. PANISH 2,387,343

. CLUTCH CONTROL F led Aug. 29, 1941 3 Sheets-Sheet 2 v INVE NTOR fZLl/Z.1 Pg m/p BY x204 ATTORNEYS 9 E..J. .PANISH 2,387,343

CLUTCH CONTROL Filed Aug. 29, 1941 3 Sheets-Sheet 3 INVENTOR rurdrz 11Pa Iii ATTORNEYS Patented on. 23, 1945 UNITED STATES PATENT, OFFICE'ctniflillot I m1. t 22322221 3 720 Application ugus ,(cl. 1.92pm!) 20Claims.

This invention relates to improvements in limit switch controlleddevices, especially in electrically driven mechanisms ior moving anoperated member toward a desired position and automatically bringingsaid member to rest in said position.

The improvements of the present invention are illustrated as applied tothe clutch control device for marine installations of my copendingapplication Serial No. 399,951, filed June 26, 1941.

In said copending application, I have disclosed a direct-currentmotor-driven mechanism for moving a reversegear or clutch operatingshaft away from an intermediate neutral position in which the clutch isdisengaged, to either one 01' a pair of opposite limiting positions inwhich the clutch is engaged for forward or reverse operation; and forreturning said clutch operating shaft from either engaged position toneutral position.

When said operating shaft reaches either limiting power circuit of themotor before neutral position ently of the armature winding, when themotor switch is opened by the limit switch device by movement of thedriven member and its associated mechanism past a predetermined point inits travel toward the position of rest.

In one variation of the invention, the magnetic braking action of themotor is increased by simultaneously shortcircuiting the terminals ofthe armature winding while the field is separately energized.

In the preferred form of the invention, the motor switch itself isoperated by a magnetic relay, controlled by a circuit including saidlimit switch which also includes the relay or the brake circuit controlmeans.

By virtue of the improvement oi the present invention, the limit switchmay be adJusted to deenergize the driving motor when the driven memberis relatively close to its desired position of rest, so that positioningof the member is rendered more accurate and reliable.

One feature of the invention is the provision of adjustment means forcontrolling the magnitude and/or duration of the braking force exertedby the motor so that the mechanism may be adis reached, the inertia ofthe'moving parts com-.

pleting the operation.

In order to insure that the operating shaft will reach neutral position,considerable excess inertia must be provided, while to overcome thisinertia and to arrest the mechanism when neutral position is reached, arelatively powerful yieldable deauxiliary retarding or braking force tothe moving parts of the mechanism upon interruption of the motorcircuit, to assist the friction of the mechanism and/or a detent meansin arresting the driven member in the desired position of rest. therebypermitting a weaker detent to bc-used. More specifically, it is anobject to provide automatic means for rendering the motor momentarilyoperative as a magnetic brake upon operation of the limit switch meanswhich deenersizes the power circuit of the motor.

This is accomplished according to the present invention by providingcircuit control means operated by a magnetic relay for momentarilyconnecting the motor held across the line, independ- Justed to positionthe operating member accurately.

As a result of the present improvements, yieldable detent meansheretofore used to arrest the driven member in the desired position maybe of much lighter construction, exerting only suflicient force, forinstance to retain the driven member in the desired position againstcasual displacement.

Since the driving force required to overcome such detent means in orderto move the member away from the said position is relatively small, aless powerful motor may be used.

The device of the present invention as illustrated herein is applied inthe marine clutch or reverse gear control system of my copendingapplication, Serial No. 399,951, filed June 26, i941.

The invention is described with reference to the switch device,controlling normal driving operations' of the motor.

mg. 4 is a wiring diagram of the clutch control system including themagnetic brake arrangement of the present invention.

Fig. 5 shows a modification of aportion of the wiring diagram of Fig, 4'for adjusting the magnitude of the braking force exerted by the motor.

Fig. 6 shows a modification of the limit switch device of Fig. 3.

The marine clutch control system of my aforesaid copending applicationcomprises a reverse gear operating mechanism, shown in Fig. 2, thehousing 20 of which encloses a direct current driving motor a gear trainincluding a worm drive coupled with the motor, and a main operstingshaft 2i driven by the gear train andcarrying a coupling 22 for engagingthe clutch or reverse gear operating shaft of a marine installation.

The clutch operating shaft, and consequently 1 the main operating shaft2i, are movable between arcuately spaced limiting positions in which theclutch is engaged for forward and reverse operation respectively,through an intermediate neutral, position in which the clutch isdisengaged. After the clutch or reverse gear has been moved to engagedposition, rotation of the shaft 2i is arrested and operation of thedriving motor is interrupted by an overload torque-responsive devicealso enclosed in the housing 20.

Motor operation is in'mrrupted when the clutch shaft is moved tointermediate neutral position by a limit switch device controlled bycams on I the shaft 28 of the operating mechanism.

In order to pgsition the clutch shaft accurately in neutral and toprevent casual drifting away from this position, an impositive yieldabledetent means is provided. The latter is illustrated in Fig. 2 ascomprising a semicircular plate 23 fixed said arcuate surface, issupported by a pivot is on the housing to and carries .a roller 2?adapted to engage said recess. The, lever 25 and roller 27 are urgedtowlard the axis of the shaft 2! by a tension spring 28 attached to thefree end of the lever, and to a bolt 29 on the housingZll. When theclutch or reverse gear is moved to neutral position, roller 27 yieldablyengages recess E l holding the shaft 2i yieldably against casualrotation.

When the motor drives the operating shaft 2i in either directiontoreengage the clutch, the tension of spring 28 is overcome and theroller 21 rides up on the arcuateperipheral surface of the plate 23.

Pivot 26 includes an adjustable eccentric bearing 3G which may besecured in any adjusted position by lock nut 3|; to adjust the positionof roller 2? to coincide with the position of recess '24 when the clutchoperating shaft is in neutral position.

The cam-operated limit switch device illustrated in Fig. 3, which isshown in neutral position, comprises an insulating plate 32 supporting apair of switches 33 and 34 having fixed contacts 33a and 34aand movablecontacts 33b and 34b respectively, Alternate closure of these switchesestablishes circuits for operating the motor in opposite directions toreturn the clutch 7 from either engaged position to neutral position.The movable contacts 33b and 3% are carried by frames 3'5 and 36respectively, supported on piv-.

ots 37 and 38, and these frames also operate limit switohesiliand 40which are closed alternately assascs with switches 33 and 34 toestablish circuits for operatingthe motor to move the clutch or reversegear to its respective engaged positions from intermediate neutralposition, and limit switches 4| and 62 for controlling advancement ofthe engine throttle.

Frames 35 and 36 carry a pair of operating levers 43 and 64 havingrollers 45 and 46 serving as cam followers. The rollers are adapted respectively to engage the peripheral surfaces of a pair of arcuate cams4i and d8, adiustably secured by bolts 5i extending through arcuateslots 59 and 50 to a circular plate 52 carried by the end'of theoperating shaft M. The said rollers are urged against the cam surfacesby a tension spring 53 joining the ends of operating levers 43 and 44. r

The cams Ill and to comprise raised peripheral surfaces 410 and 48a,terminating in shoulders 41b and 486 which are respectively adapted toengage rollers or 46 upon rotation 0f the shaft 2! clockwise orcounterclockwise from the illustrated neutral position, whereby switches33 or 36 are closed. Upon return to neutral position, the cams releasethe said rollers before neutralposltion is reached, allowing levers :33or 46 to move inward under the influence of spring 53 until the rollersengage the edge of the plate 52 or the inner surfaces die or 680 of thesaid cams,'whereby the switches 33 and 34 are opened and the motorcircui't deenergized. Since this occurs before neutral position isreached, the inertia of the moving parts of the mechanism is utilized tocomplete the movementof the operating shaft 2i to neutral position.

According to the present invention, automatic circuit control means isprovided to cause the motor to apply a magnetic drag sufllcient toovercome the inertia of the moving parts within a relatively short timeafter the motor circuit is opened, said drag or braking force serving toovercome the inertia of moving parts and to bring the clutch operatingshaft substantially to rest in neutral position.

-"This means comprises an automatic switch device, adapted, when themotor circuit is opened by the limit switches 33 or 36 during operationof the reverse gear to neutral position, to alter the motor circuit fora short period of time, so that the field of the motor acts as amagnetic brake on the armature. This may be accomplished, for instanceby energizing the field of the motor. either while the armature windingis dee'nerglzed, or preferably, while the armature is shortcircuited. r

A form of automatic switch device suitable for the said purpose isillustrated in Fig. 1. It is enclosed in a casing 54'which may belocated in any convenient position, preferably adjacent the re versingswitch of the motor of the control sys'. tem. The device comprises anadjustable contact 55 carried by a resilient strip 56 which is pivotallysupported on the casing at 51. The head of an adjustment screw .58engagesstrip 56 intermediate its ends, while the opposite end of thescrew is threaded into a bracket 59 fixed to the casing 54. Acompression spring 6| engaging the bracket 59 urges strip 56 against thedepending head of the adjustment screw, and by turning the screw 58 inopposite directions, contact 55 may beraised or lowered.

A movable contact 62, adapted to close a circult by engaging contact 55,is carried by a resilient strip 63 pivoted at 64 to the casing 545. Themovable end of strip 63 is joined by a pair of toggle links 65 and 66 toa ilxed supporting pivot 61 on the casing. The elbow Joint of the saidpair g or. links isattached by a link 68 to the armature 69 of asolenoid 19. Upon energization of the solenoid, the armature 69 moves tothe right, po-

-A control station I99 is provided with a manual controller m pivotallymounted at :I92 and havsitioning the togglelinks in'the mannerindicatedby dot and dash lines, whereby contacts 55 and 82 are separated; whilewhen the solenoid I9 is deenergized, a tensionspring ll attached tocasing 54 at I2 and-tothe junction ofthe toggle links 65 and 66 normallyurges the linkage to the left,

and moves them to the, illustrated position,

whereby contact 62js again disengaged from contact 55. During operationof the linkage in' either 7 direction, contact 62 is raised, and thenlowered engaging contact 55ior a short period of time, the

extent of which may be: adjusted by raising or lowering the screw 58.

If more than one circuit is to'be closed to provide the desired brakingeffect, a second pair of contacts I: and 14 indicated in Fig. 1 bydotted lines may be provided operated simultaneously --with contacts and62 and similarly adJustable bymeans oi the screw 58. In the wiringdiagram of Fig. 4, application of the above-described control device tothe control a system of my copending application Serial-No. 399,951,filed June 26, 1941, is shown. Power-is supplied from a battery89, thedriving motor M being series wound to .provide high starting.

torque. Thefleld winding 8| is permanently connected to the positivepole of the battery 89, while ing a bridging contactor I 93 adapted insucces- =sive positions of the controller to close circuits througharcua'tely spaced pairs of contacts I94, I95 and I96 forinitiating'operation oi theidriving'motor. The controller "II alsooperates the 1 tralposition. The-circuit through contacts I98 initiatesmovement o'f the clutch to forward engaged position, whilethe circuitthrough contacts I96 initiates clutch operations inreve'rse engagedposition; I

A pair of solenoids I91, the circuits of which are controlledrespectively by limit switches M and 42, when energized preventm'ovementoi the controller beyond the said contact pairs, thus is in neutralposition as illustrated, limit switches I switches 82 and 83', onopposite sides of the arma- Y ture 81, establish when closed, a circuitfrom the field winding 8| through the armature to the I negative pole ofthe battery, traversing lead 84, v switch 82, lead 85, armature 81, lead89, switch 83, leads 90, 9|, and 92. Closure of switches 82 and 83 isthus adapted to operate the motor for rotation in"iorward" direction,for instance, for

'. moving'the clutchaway from reverse-engaged or neutral position,toward forward-engaged posi tion.

- Switches 93 and 9 4 are similarly adapted'upon closure to establish acircuit from the field wind ing through the armature in the oppositedirection to the negative pole of the battery, lead 84, switch 93, lead89, armature winding 81, leads 95 and- 95, switch 94, and leads 9| and.92.'

Since the direction of the current through the armature winding isreversed, the motor will rotate in the opposite or "reverse direction,for in stance to move the-clutch or reverse gear away fromforward-engaged or neutral position, toward reverse-engaged position.

Motor switches 82, 83, 93 and '94 are normally urged to open-circuitposition, andif desired, a mechanical interlock preventing simultaneousclosure of the two pairs of switches may be pro- -vided as is usual inmotor reversing switches.

For closing switches 82 and 83,-electromagnets 96 and 91 are provided,each adaptedupon energization to close the switches. The electromagnet96 is used to move the clutch to'iorward enaged position, whileelectromagnet 91 is utilized -'-to operate the clutch from reverseengaged to electromagnets 98 neutral position. Similarly, 'and 99 areprovided, each adapted to close switches 93 and 94-. Electromagnet: 98is use'd when the clutch is to beoperated to reverse enpreventingadvancement of the throttle, until the clu is tullyengaged. Namely, whenthe clutch 4| and 42 are -closedgsolenoids I91 being energized'. Whenthe controller is moved to contacts I94 and I96, the clutch mechanismmoves towa'rd' one of its engaged positions, and this causes cams 41 or48 to open limit switch 4I or 42 deenergizing the corresponding solenoidI91 and releasing the controller for advancement of-the throttle.

traversing When theclutch is again returned to neutral position, cams"and 48 reset limit switches 4 I and 42 to reenergize solenoids I91.

When the clutch is in neutral position, limit switches" 39 and 49 areclosed, energizing relays I98 and I99 which hold relay switches H9 and Y-.I I I closed. This establishes a circuit from con-- tactors I94 andI96 respectively to electromagnets 96am! 98. Upon completionot oneoithese circuits by appropriate movement of thecontroller I9'I,electromagnet 96. or 98 closes switches 82 and 83, or 93 and 94, causingthe motor to move the clutch toward one of its engaged positions.Holding switches. I I2 or H8 are closed simultaneously with the saidmotor switches and maintain energization of the electromagnet. Duringoperation of the mechanism toward the limiting position, cams 41 and '48open limit switches 39 or 49, deenergizing relay I98 or I99,

gaged position, while electromagnet 991s energized when the clutch ismoved from forward engaged-position to neutral position. Theimprovements of the present invention'cooperate princi pally withelectromagnets 91 and 99.

cult through electromagnet 96 or 98 .is main- I tained solely byholdings witch ,I I2 or I :3.

After the clutch-operating shaft 2I reaches its limiting position,torque switch II4, Included'in the circuit of 'electromagnets 96 and 98opens in response to continued'rotation of the motor, thus deenergizi'ngthe electromagnetsand opening the motor switches.

. With the clutch 'in either engaged position,

' movement or the controller I M to its midposition, wherein contactorI93 bridges the intermediate pair of contacts I; establishes acircuitfrom the positive pole of the battery through lead II-5 (includingmasterswitch H6) to contacts I95, then through lead I II to-the eleetromagnets91 and 99. "The circuit from electromagnet 91 to the negative pole ofthe battery follows leads us and us to switch' fl, while the circuitfrom electromagnet 99 includlng leads I29 and I2I terminates at limitswitch 33. 'The switches 83 and-34 are'connectcd bylead m and lead a: te

I the negative pole, or the battery.

.When the clutch is in 'iorward engaged D 51- tion,ec am "which hasrotated counterclockwise,

cuit through "electromagnet 99 while 34 in the circuit orelectromagnet'fl remains open;

Upon movement 0! thecontroller to neutral position, wherein contacts" sare engaged, thecircuit to electromagnet 99 is'compieted, causing motorswitches s: and u to close and initiating motor'operation to move theclutch toward neum1. Similarly, if the clutch is originally inreverse-engaged position, cam 48"will have closed limit switch I,leaving limit Switch '3 open, and

of the solenoid armature as, the shunt'circuit through contacts 56 and62 13 opened and the motor is fully energized to move the clutch towward neutral position. l

' holds limit s'witch a; closed, establishing the clr- 6 I As theclutchapproaches neutral position, cam

41 or 48 releases limit switch 33' or 34 and interrupts the circuit notonly to electromagnet 91 or 99 but also to the solenoid 10. The motorswitches 82 and-83 or 93 and 94 are opened, interrupting 11 the circuitthrough-the armature winding. At the same 'time'solenoidarmature 69 isreleased and is moved to the left by spring H reengaging contacts-55 and62 momentarily. The field winding of the motor is thereby energized,while the arma ture circuit is open, and the-field of the motordirection, cam 41 or 48 releases corresponding limit switch 33 or 34,thereby deenergizing the electromagnet-9'l or 99, and opening-the motorswitches. At the same time, the ca'msreset limit positions.

In auxiliary control device of the present inventiomtthe solenoid"comprises twowindings,

' 10a and 10b, connected respectively in parallel effect longerorshorter. Thus, the device may be with electromagnets 91 and. Asillustrated inv 4,.these two windings have.a common terexerts? amagnetic drag-or, braking action on the armature as long as the contactsare engaged.

-The saidbraking actionopposes the inertia of the moving vparts ofthemechanism, bringing the mechanism more rapidlytq rest.

As the movement of solenoid armature 69 to the leftis completedunder theinfluence of spring ll, contacts 55 and 62 are again separated, opening'the circuit through the' motor field-and releasing the braking force. Iswitches to, u, u and 42 in their original closed 2 By adjustingthespacing between contacts and 92 by means of screw 58, the durationofthe closure 01' said contacts maybe increased or decreased to renderthe duration of the braking inal'connected by lead 122' to lead 1l'lgwhicli is 1 common to eachot the two electromagnets 9] and i 99. Theopposite end or winding Illa is connected by lead I 23 to lead 8. Joinedto the opposite terminal' of electromagnet 91, while the opposite end ofwinding- Nb-is connected by lead I24 to lead |29 of electromagnet 99.

one or; the solenoid windings-10a or "h taneously energized, causingarmature-19.9 to be moved'to the right, and bringing contacts 55 andAccordingly,- when; eitheroi the electromagnets, "or 99 is energized, oregulated, and accordingly the magnitude of the 62. temporarily intoengagement:- while upon de- I andjl' are similarly engaged'momenta'rily.

- Contacts 55 and 62, which are joined respecv y to lead 84 by lead I25,and to .lead 92 by rially increased by short-circuiting the armaturelead I29, are adapted when engaged to complete a shunt circuit from thefield winding, around motor switches 82, 83, 93-and 94 and armature isfirst started, and theinltial torque of the motor 5 shown in dottedlines in Fig. 4 connected respec- In operating thecontrolsyst'em toreturn the I clutch to neutral from either engaged position,

the controller i9! is moved to its midposition wherein contactor I99bridges contacts, I95, clos ing the circuit to' electromagnet '99 or 91,and simultaneously energizing the circuit to' solenoid winding llla or"b. Energizatlon of the electromagnet closes the motor switches 93 and94, or "and ,while the solenoid moves its armature 69 to the rightclosing the circuit through contacts and 92 momentarily. As long asthiscir-- adjusted tobring the mechanism to rest substantially atneutral position.'

Further means foradlustin'g the braking eiIect is provided in avariation of the device illustrated 3' in Fig. 5. A variableresistance-fills inserted in the circuit of the solenoidcontrolledswitch con- 1v tacts 65.;snd 62, that is in lead I er-lzs. Byadjustingthisj resistance, the current through the .field winding duringthe braking action may be braking force may be reduced or increased atwill.

An advantage of this'arrangement lies in the energization ofelectromagnet'fl or 99, the solemotor switohea'an increased proportionof current flows through the armature when the motor i correspondinglyincreased.

The braking force or the motor can be mateduring energization ofthefleld, after the motor of the invention, this may be accomplished byproviding a circuit comprising leads I28 and I29,

tively to leads 9! and 99 which supply the brushes ofthe motor, andincluding a switch comprising contacts" and. 74 whichare operatedsimilarly and simultaneously with contacts 65 and 62 by o solenoid 19.The resistance I21 may also be included s before in the field windingclrcuit,.to control the magnitude of the braking force; but

in this'case, the efiect of the said resistance to increase the startingtorque of the motor durin Ienergizatlon oi the field by solenoidswitches cult is closed. the field winding of the motor is .fullyenergized, butIthearmature-and its circuit,

' tion is relatively short, theleii'ec't is of no great c nsequence.Upon completion oi the movement and 62 will be considerably reduced.However,

since this condition is of short duration, it is of nomaterial-disadvantage.

:By provision of the aforesaid magnetic braking \mcmdmg theswitchesreceive '3 7odevioe, it is no longer necessary that the yield-.able dete means, comprising roller 21 and re-- cessed sec r plate 29should be strong enough to arrest movement of the clutchmember innoncient force to retain the movable parts against casual drifting outof neutral position. Moreover, cams 41 and 40 may be adjusted to openthe limit switches 38 or 14 to deenergize the motor when the clutch hasbeen operated almost to neutral positio so that the clutch remains underthe control of the motor for substantially its entire clutch-disengagingoperation.

To permit such adjustment, without disturbing the operation oflimitswitches 4| and 42 which control throttle-adjusting operation ofthe con I34, mounted on plate 52 and engaging cam followers I25 and I"on the operating arms of said switches. By adjusting cams I33 and I34,limit switches 4i and 42 may be made to release the controller IIH forcontrol of the throttle after the clutch is engaged, while cams 41 and48 may be adjusted to open limit switches 33 and 34 as close to neutralposition as desired.

While the device of the present invention has .been described as appliedto the marine clutc control system or my copending application, it maybe similarly used to control the stopping of any motor driven member,where a limit switch is utilized to automatically interrupt operation ofthe driving motor when the member approaches the position in which it isdesired to arrest its motion.

Variations and modifications may be made within the scope of thisinvention and portions of the improvements may be used without others. Iclaim:

, 1. In combination with a direct current motor having an armature andfield winding, and an energizing circuit therefor includingcurrent.supply means, power control means for interrupting said circuit;control means for energizing the field winding from said current supplymeans independently of the armature whereby a magnetic brake is appliedby the field to the armature and automatic means rendering said controlmeans operative upon operation of said power control means to interruptthe motor circuit,

2. In combination with a direct current motor having an armature andfield winding, and an energizing circuit therefor including currentsupply means, power control means for interrupting said circuit; controlmeans for energizing the field winding from said current supply meansindependently of the armature; automatic means rendering said controlmeans operative upon operation of said power control means to interruptthe motor circuit, whereby the field winding exerts a magnetic drag onthe armature; and means for varying the magnitude of the braking effeciproduced thereby.

3. In combination with a direct current motor having an armatureanclheld winding. and an energizing circuit therefor including currentsupply means, power cant i means for interrupting said circuit; 'controimeans for energizing the field winding i'rom said current supply meansindependently of the armature, and simultaneously short-circuitingarmature terminals; and automatic means rendering said control meansoperative upon operation of said power control. means to interrupt themotor circuit.

v4. In combination with a direct current motor having an armature andfield winding, and an energizing circuit therefor including currentsupply means, power control means for interrupting said circuit; controlmeans for energizing the field winding from said current supply meansindependently oi the armature; and automatic means for rendering saidcontrol means temporarily operative for a predetermined time intervalupon operation of said power control means to interrupt the motorcircuit.

5. In combination with a direct current motor having an armature andfield winding, and an energizing circuit therefor including currentsupply means, power control means for interrupting said circuit; controlmeans for energizing the field winding from said current supply meansindependently oi the armature; automatic means for rendering saidcontrol means operative upon operation of said power control means tointerrupt the motor circuit; and means for adjusting the magnitude ofthe field current for independent energization thereof.

6. In combination with a direct current motor having field and armaturewindings and a power circuit for energization thereof including currentsupply means, means for opening and closing the power circuit; a,circuit for energizing the field winding from said current supply meansinde pendently of the armature; automatic means for energizing thelatter circuit upon opening of the power circuit; and means for varyingthe resistance of. said independent field circuit for controlling themagnitude of the field current dur' ing independent energiza'tionthereof.

7. In combination with a direct current motor having field and armaturewindings and a power circuit for energization thereof including currentsupply means, means for opening and closing the power circuit; asecondary circuit for energizing the field winding from said currentsupply means independently of the armature; a switch the secondarycircuit comprising a pair of contacts; automatic means for moving saidcontacts toward and away from each other for momentary engagementthereof to close said secondary circuit upon opening of the powercircuit, whereby said secondary field circuit is temporarily energized;and means for adjusting the spacing of said contacts to control theduration of their engagement.

8. In combination with a direct current motor having field and armaturewindings and a power circuit for energization thereof including currentsupply means, switch means for opening and. c1osing the power circuit;electromagnetic relay means for operating said switch means; a secondarycircuit for energizing the field winding from said. current supply meansindependently of the ar mature; switch means for opening and closing thesecondary circuit; electromagnetic relay means for operating the latterswitch means; a

control circuit common to both of said electrm magnetic relay means; andmeans for operating said control circuit to open said power circuitswitch, said operation at the same time closing said secondary fieldcircuit switch to ener ze the field of the motor independently of thearmature.

.9. In combination with a series-woimd direct current motor having anarmature and finial wind.- ing, a power circuit therefor includingswitch meansconnected to a terminal of the armature; an electromagneticrelay for opening andciosing tive upon deenergizatlon trolled switchmeans upon opening as well as upon closing of said power circuit by saidrelay-com trolled switch means.

10. In combination with a series-wound direct current motor having anarmature and field winding, a power circuit therefor including switchmeans connected to a terminal of the armature; an electromagnetic relayfor opening and closing said switch means; a shunt circuit around saidarmature and said switch means for energizing the field independently ofthe armature; a switch controlling said shunt circuit; a solenoidadapted, upon ener ization, and similarly upon deenergization, to firstclose and then reopen the latter switch means; a control circuit commonto said electromagnetic relay means and to said solenoid;

' means for controlling energization of said control said means.effecting temporary closure.

circuit, of said field circuit by said solenoid-controlled switch meansupon opening as well as upon closing of said power circuit by saidrelay-controlled switch means;- and means for varying the resistance ofsaid shunt circuit, whereby the field current and armature current maybe varied during closm'e of the solenoid-controlled switch means. r

11. A device for moving a driven member to and from opposite operatingpositions relativeto an intermediate idling position, having an electricdriving motor with an armature and field winding, and a power circuitfor energizing the motor to I move said member toward saidxidlingposition;

means for mechanically yieldingly arresting and holding said drivenmember in idling position; limit switchm'eans for interrupting saidpower circuit when the driven member position, adjacent said idlingposition, wherein the movingparts of the device have suflicient excessinertia to overcome said arresting and holding means andoverrun .theidling position; and automatic circuit control means rendered operaassauts permit the driven member to be arrested in 1 position by saidyielding means.

- 13. a device for moving a driven member to and from opposite operatingpositions relative to an intermediate idling position, having anelectric driving motor with an armature and field wind-' ing means andoverrun the idling position; automatic circuit control means renderedoperative upon deenergization of said power circuit to momentarilyenergize the field winding ofthe motor independentlyof the armature, andthereby to produce a magnetic drag on the armature for overcoming saidexces inertia; and means for controlling the magnitude of said magneticdrag to that necessary to cause the driven memberto be arrested inidling position.

14. A device for moving a driven member to and from opposite operatingpositions relative to an intermediate idling position, having anelectric driving motor with an armature and field winding; a powercircuit for energizing the motor to move said member toward said idlingposition; means for mechanically yieldingly arresting and holding saiddriven member in idling position;

limit switch means for interrupting said power circuit when the drivenmember reaches a control position, adjacent said idling position,wherein the moving parts of the device have sufiicient excess inertia toovercome said arresting and holding means and overrun the idlingposition; and automatic circuit control means rendered operative upondeenergization of said power circuit for reaches a control momentarilyenergizing the field winding of the motor independently of the armatureand for simultaneo'usly shortcircuiting the armature winding, whereby amagnetic drag on the armature is produced for overcoming said excessinertia and the driven member is arrested in idling position.

15. A device for moving a driven member to and from'opposite operatingpositions relative to an tive upon deenergiz'ation of said power circuitfor momentarily energizing the field winding of the motor independentlyof the armature, whereby a magnetic drag on the armature is produced forovercoming said excess inertia and the driven member is arrested inidling position.

12. A device for moving a driven member to and from opposite operatingpositions relative to an intermediate idling position, having anelectric driving motor with an armature and field wind ing; a power;circuit for energizing the motor to move said member toward said idlingposition; means for mechanically yieldingly-arrestingand holding saiddriven memberin idling position;

limit switch means for interrupting said power circuit when the drivenmember reaches a control position adjacent said stop position whereinthe moving parts of the device have sufficient excess inertia to overrunthe idling position; and automatic circuit control means renderedopera-- ,o1 said power circuit for momentarily producing a magnetic dragon the armature for overcoming said excess inertia and 76.

intermediate idling position,-having anelectric driving motor with anarmature and field winding; a power circuit for energizing the motor tomove said member toward said idling position;

emeans for mechanically yieldingly arresting and holding said drivenmember inidling position; limit switch means for interrupting said powercircuit when the driven member reaches a. control position, adjacentsaid idling position, wherein the moving parts of the device havesufiicient excess inertia to overrun the idling position; automaticcircuit control means, rendered operative upon deenergization of saidpower circuit for energizing the field winding of the motorindependently of the armature .to produce a magnetic drag on thearmature for overcoming said excess inertia and permit the driven memberto be arrested in idling position by said yielding means; and means -forvarying the resistance of the field circuit during.-

independent energization thereof for adjusting the magnitude of 'saidmagnetic drag on the armature.

16. A device for moving a driven member to and from opposite operatingpositions relative to an intermediate idling I position, having anelectric driving motor with an armature and field winding; a powercircuit for energizing said motor to move said member toward said idlingposition; switch means for controlling energization of said powercircuit; electromagnetic relay means for operating said switch means; anauxiliary circuit for energizing the field of said motor independentlyof the armature; switch means controlling the latter circuit;electromagnetic relay means for operating the latter switch means; acontrol circuit common to both of said electromagnetic relay means;means for mechanically yieldingly arresting and holding said drivenmember in idling position; and-limit switch means in said controlcircuit, automatically operated when the driven member reaches a controlposition adjacent said idling position, wherein the moving parts of thedevic have sufilcient excess inertia to overrun the idling position,said limit switch inertia and the driven member is arrested in idlingposition. I

1'7. A- device for moving a driven member to and from opposite operatingpositions relative to an intermediate idling or neutral position,comprising a direct-current series-wound motor therefor havingarmatureand field windings; a

power circuit for energizing the motor including switch means connectedto a terminal of the armature; a shunt circuit around said armature andsaid switch means for energizing the field independently of thearmature; control means for said power circuit, and for said shuntcircuit;

means for mechanically yieldingly arresting and holding said drivenmember in idling position; and limit switch means operative upon saiddriven m'ember'reaching a control position adjacent said neutralposition wherein the moving parts of the device have sufficient excessinertia to overcome said arresting and holding means and overrun saidneutral position, said limit switch means operatingsaid control means toopen said power circuit switch and to cause momentary energization ofsaid shunt circuit, whereby said field winding is energizedindependently of the arma: ture, and a magnetic drag on the armature isproduced for overcoming said excess inertia and causing the drivenmember to be arrested in idling position.

18. A device for moving a driven member to a predetermined stopposition, comprising a directcurrent series-wound driving motor, havingan armature and field winding; a power circuit for energizing the motorto move said member toward said stop position, said circuit includingswitch means connected to a terminal oi the armature; an electromagneticrelay for opening and closing said switch means; a shunt circuit aroundsaid armature and said switch means ior energizing the fieldindependently of the armature; a switch controlling said shunt circuit;a solenoid adapted upon energization, and similarly upon deenergization,to first close and then reopen the latter switch means; a controlcircuit common to said electromagnetic relay means and to said solenoid;limit switch means in said control circuit operated upon said drivenmember reaching a control position adjacent said stop position, whereinthe moving parts of the device have sufllcieni excess inertia to overrunthe stop position, operation of said limit switch means effectingdeenergization of said power circuit by said relay-controlled switchmeans, and temporary energization of said shunt circuit by operation ofsaid solenoidcontrolled switch means, whereby the field winding of themotor is temporarily energized, and a magnetic drag on the armature isproduced for overcoming said excess inertia; and means for varying theresistance of said shunt circuit, whereby the field current and armaturecurrent may be varied during temporary closure oi thesolenoid-controlled switch means for regulating the magnitude of saidmagnetic drag.

19. In combination with a reverse gear and clutch device having forwardand rearward operating positions and a neutral or idle position betweensaid operating positions, operating means for said device including anelectric motor and circuits therefor opened, closed and reversed forstopping, operating and reversing said motor; limit switch means forautomatically opening said circuit to the motor when the operating meansapproaches neutral position from either the forward or rearwardoperating position of the device; and means for causing a momentaryelectromagnetic braking force to be applied to the device after themotor operating circuit is opened and as said operating neutral positionis reached for dissipating the momentum of the parts of the device andoperating means and prevent overrunning beyond the neutral position.

20. In combination with a reverse gear and clutch device having forwardand rearward operating positions and a neutral or idle position betweensaid operating positions, operating means for said device including anelectric motor and circuits therefor opened, closed and reversed forstopping, operating and reversing said motor; limit switch means forautomatically opening said circuit to the motor when the operating meansapproaches neutral position from either the forward or rearwardoperatingposition of the device; mechanical means for locating thedevice in neutral position and maintaining the same so positionedagainst casual displacement; and means for causing a momentaryelectromagnetic braking force to be applied on the device after themotoroperating circuit is opened and before said mechanical means acts fordissipating the momentum of the parts of the device and operating meansand prevent overrunning beyond the said mechanical means.

position controlled by IRWIN J. PARISH.

